1) Field of Invention
The invention relates to a golf training aid, and more particularly to a training device that enables a golfer to accurately determine the direction in which a golf ball will be hit when properly struck, and an aid that assists the golfer in properly aligning his feet with respect to the ball.
2) Prior Art
In playing the game of golf, a golfer must properly align his body with respect to the ball to accurately hit it to a desired location on the course. It is not easy for the golfer to position his stance such that the alignment is attained. There have been recent advances using laser technology that help a golfer align his position with respect to the ball, and with respect to the desired direction that the golfer wishes to hit the ball. In U.S. Pat. No. 6,007,436 to Phillip Mark, there is disclosed a method for employing light from a laser light beam source to assist in aiming a golf ball and device therefor. In the invention the golfer holds the laser light beam source directly over the golf ball and rotates the source until the golfer believes that it is pointed toward the desired direction. The source creates three lines on the ground. A first line bisects the ball and points in the direction that the golfer wishes to hit the ball. A second line is parallel to the first line, so that the golfer can align his feet. A third line is orthogonal to the first line and the second line, such that the shaft of the club can be aligned substantially parallel with the third line.
A limitation of Phillip Mark's invention is that the golfer must accurately rotate the device over the ball so that the first light beam is accurately pointed in the desired direction. A second limitation is that the second line, which helps the golfer align his feet, is a function of the height at which the golfer holds the laser-training device. The higher the device, the greater the distance between the first line and the second line; and in order to achieve reproducible results, the golfer must always hold the light beam device at the same height. A third limitation is that, as shown, the lines are only created while the golfer is holding the laser light beam source. As soon as the golfer picks up his club to hit the ball, then he must put down or pocket the laser light beam source. Another limitation is that the golfer has to move with respect to the ball (versus the conventional method of training where the golfer positions the ball), and the invention doesn't relate the position of the ball with the position of the golfer's lead foot. An advantage of Phillip Mark's invention is that it is portable and can be easily transported to the golf course or the driving range.
What is needed is a training device that does not require the golfer to hold the device when addressing the ball, where the training device can be set up and/or teed into the ground in a stationary position, and therein produces a feet alignment directional laser line. The feet alignment directional laser line can then be adjusted by sighting down the line, and rotating the device such that the line has the desired coincident orientation. Furthermore, what is needed is a training device that in applications where the ball has a fixed position (e.g. a driving range), the feet alignment directional laser line can be adjusted such that the distance from the ball to the feet alignment laser line is adjustable to accommodate clubs having different shaft lengths, and people having different dimensions and styles of play (i.e., tall or short, and how much they are comfortable leaning forward or standing upright). Further, what is needed is a feet to ball laser line that is orthogonal to the feet alignment directional laser line, where the feet to ball laser line provides the golfer a stationary visible reference to properly align his feet, and in particular his lead foot, with respect to the golf ball. The feet to ball laser line should provide a reference where the golfer will know that for any given club what is the desired position of the ball with respect to the feet to ball laser line. For instance, for a driver the ball is typically in front of the front of the feet to ball laser line, and consequently close to the golfer's lead foot toe, and for a fairway wood the ball is typically on or behind the feet to ball laser line, and consequently further back and closer to the golfer's heel.
Another desired feature of the training device is that it can be used to quantify the golfer's club head speed, as the club head speed is strongly indicative of the distance the struck ball will travel.